(a) Field of the Invention
The present invention relates to an improved gravity cooling coil device which comprises at least two columns of fin coils positioned side by side and defining between them a substantially unobstructed vertical air passage thereby preventing freeze-up of the cooling coils and pemitting closer spacing thereof, permitting a substantial improvement in the BTU per square inch area of cooling coil.
(b) Description of Prior Art
Gravity cooling coils are known. However, such coils usually comprise a cooling block formed of a serpentine arrangement of fin coils with the fins and the coils being spaced such as to form a substantially solid rectangular evaporator. The evaporator is supported above a large condensate collecting pan which permits ventilation therethrough whereby the cold air can pass between the various collecting channels of the pan to cool the space thereunder. This makes for a very bulky structure which is difficult to install and which occupies much space as the evaporator must be positioned a certain distance from the ceiling of a room whereby to permit proper air ventilation around the evaporator whereby environmental warm air will cool and fall by gravity. The pan is also spaced from the evaporator and is an obstruction to the convection air flow, thus reducing the efficiency of the evaporator, and further causes the evaporator to freeze up. Another problem is that on the top side of the pan there is provided a very cold mass whilst on the bottom side of the pan the air is substantially warmer. Because of this, the condensate collection pan must be constructed with double-channels whereby the condensate does not freeze up in the pan.
However, such bulky gravity coil devices have an advantage over the forced air cooling system in that they do not use a fan and motor to drive the air through the evaporator. The disadvantages of using a motor are many such as it provides a still bulkier construction, the operation of the device is noisy, it consumes energy, it requires more maintenance, it is drafty, and the effect of the blower causes dehydration of meats and plants which may be stored in the cold room. However, it is often not possible to install gravity coil devices for the reason that there is insufficient space adjacent a ceiling of a cold room enclosure to install the device. Most cold rooms prefabricated today have very low ceilings averaging about 7 feet 6 inches. Therefore, there is insufficient space to install such devices and it is necessary to revert to other types of cooling systems.